In vertebrates, sexual differentiation of the reproductive system and brain is tightly orchestrated by organizational and activational effects of endogenous hormones. In mammals and birds, the organizational period is typified by a surge of sex hormones during differentiation of specific neural circuits; whereas activational effects are dependent upon later increases in these same hormones at sexual maturation. Depending on the reproductive organ or brain region, initial programming events may be modulated by androgens or require conversion of androgens to estrogens. The prevailing notion based upon findings in mammalian models is that male brain is sculpted to undergo masculinization and defeminization. In absence of these responses, the female brain develops. While timing of organizational and activational events vary across taxa, there are shared features. Further, exposure of different animal models to environmental chemicals such as xenoestrogens such as bisphenol A-BPA and ethinylestradiol-EE2, gestagens, and thyroid hormone disruptors, broadly classified as neuroendocrine disrupting chemicals (NED), during these critical periods may result in similar alterations in brain structure, function, and consequently, behaviors. Organizational effects of neuroendocrine systems in mammals and birds appear to be permanent, whereas teleost fish neuroendocrine systems exhibit plasticity. While there are fewer NED studies in amphibians and reptiles, data suggest that NED disrupt normal organizational-activational effects of endogenous hormones, although it remains to be determined if these disturbances are reversible. The aim of this review is to examine how various environmental chemicals may interrupt normal organizational and activational events in poikilothermic vertebrates. By altering such processes, these chemicals may affect reproductive health of an animal and result in compromised populations and ecosystem-level effects.

中文翻译：

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poikilothermic脊椎动物的组织和激活激素编程的神经内分泌破坏。

在脊椎动物中，内源激素的组织和激活作用紧密协调了生殖系统和大脑的性别分化。在哺乳动物和鸟类中，组织期的特征是特定神经回路分化过程中性激素的激增。而激活作用取决于性成熟后这些相同激素的增加。根据生殖器官或大脑区域的不同，最初的编程事件可能受雄激素调节或需要将雄激素转化为雌激素。基于哺乳动物模型发现的普遍观念是，男性大脑经过雕刻以进行男性化和女性化。如果没有这些反应，女性大脑就会发育。尽管组织和激活事件的发生时间因类群而异，有共享的功能。此外，在这些关键时期，将不同动物模型暴露于环境化学物质（例如双酚A-BPA和炔雌醇-EE2等异种雌激素），孕激素和甲状腺激素破坏剂（在广义上被归类为神经内分泌破坏化学品（NED））可能会导致类似的变化在大脑结构，功能以及行为方面。神经内分泌系统在哺乳动物和鸟类中的组织作用似乎是永久性的，而硬骨鱼类神经内分泌系统则表现出可塑性。尽管两栖动物和爬行动物的NED研究较少，但数据表明NED会破坏内源性激素的正常组织激活作用，尽管尚不确定这些干扰是否可逆。这篇综述的目的是研究各种环境化学物质如何干扰poikilothermic脊椎动物的正常组织和激活事件。通过改变这些过程，这些化学物质可能会影响动物的生殖健康，并导致种群数量下降和生态系统影响。